Heterojunction array based ultraviolet detector and manufacturing method thereof

Abstract

The invention discloses a heterojunction array based ultraviolet detector and a manufacturing method thereof. The detector comprises a substrate and a conductive film; an Sm2O3@ZnO heterojunction array which is used as an ultraviolet absorbing layer and at least one N-type ohmic electrode are arranged on the conductive film; at least one P-type ohmic electrode is arranged on the Sm2O3@ZnO heterojunction array; and the Sm2O3@ZnO heterojunction array is composed of a ZnO nano-tube array and an Sm2O3 nano-wire filled in the ZnO nano-tube. The core structure of the detector provided by the invention is the heterojunction array consisting of the ZnO nano-tube array and the Sm2O3 nano-wire penetrating the ZnO nano-tube; the usage rate of a photo-generated carrier can be sufficiently improved, and the heterojunction array based ultraviolet detector has the advantages of high external quantum efficiency and flexibility, small volume and the like.

Description

technical field [0001] The invention relates to an ultraviolet light detector technology, in particular to a heterojunction array-based ultraviolet light detector for ultraviolet light detection and a preparation method thereof. Background technique [0002] Ultraviolet light detectors have been widely used in military and civilian fields because of their strong anti-interference ability and other advantages. Because traditional single crystal Si-based semiconductor materials have no selective absorption for ultraviolet light, expensive filters must be used, resulting in high production costs for single crystal Si-based ultraviolet detectors, which are difficult to meet the needs of the civilian market. Therefore, at present, people mainly focus on junction devices made of wide bandgap semiconductor materials, such as (Al)GaN, SiC, ZnO, diamond junction devices, etc., and the corresponding research is also mainly concentrated on single crystal devices. Due to the complex pr...

AI Technical Summary

Problems solved by technology

[0005] 1. The heterojunction structure of traditional polycrystalline thin film junction devices is similar to that of single crystal junction devices, and the heterojunction interfaces are common planar contacts. Therefore, the area of ​​the space charge region distributed near the contact surface is small, which is harmful to light generation. Limited separation of electron-hole pairs;

[0006] 2. The excessively high grain boundary and defect density in the polycrystalline film seriously hinder the diffusion of photogenerated electrons to the conductive substrate or metal electrode, so that a large number of photogenerated electron-hole pairs are lost due to recombination before they diffuse to the electrode. Lose;

[0007] 3. A large number of defects in the polycrystalline film serve as the recombination center of photogenerated electron-hole pairs, which also seriously reduces the lifetime of photogenerated carriers.

However, the lifetime of photogenerated carriers is limited

Once the diffusion time of photogenerated carriers is longer than its lifetime, this part of photogenerated carriers will be lost

Images